# -*- coding: utf-8 -*-
"""
@Project: base_python
@File: game_functions.py
@Author: PC
@Date: 2025/2/13
@Description: 
"""
import sys
import pygame
from bullet import Bullet
from alien import Alien
from time import sleep

def check_keydown_events(event,ai_settings, screen, ship, bullets):
    """响应按键"""
    
    if event.key == pygame.K_q:
        sys.exit()
    elif event.key == pygame.K_RIGHT:
        ship.moving_right = True
    elif event.key == pygame.K_LEFT:
        ship.moving_left = True
    elif event.key == pygame.K_SPACE:
        # 创建一颗子弹，并将其加入到编组bullets中
        fire_bullet(ai_settings, screen, ship, bullets) 


def fire_bullet(ai_settings, screen, ship, bullets):
    """如果还没有到达限制，就发射一颗子弹"""
    # 创建一颗子弹，并将其加入到编组bullets中
    if len(bullets) < ai_settings.bullets_allowed:
        new_bullet = Bullet(ai_settings, screen, ship)
        bullets.add(new_bullet)             
def check_keyup_events(event, ship):
    """
    响应松开键盘事件
    :param event: 键盘事件对象，用于检测哪个键被松开
    :param ai_ship: 飞船对象，根据键盘事件更新飞船的移动状态
    """
    # 当玩家松开右箭头键时，停止向右移动飞船
    if event.key == pygame.K_RIGHT:
        ship.moving_right = False
    # 当玩家松开左箭头键时，停止向左移动飞船
    elif event.key == pygame.K_LEFT:
        ship.moving_left = False


def check_events(ai_settings,screen,stats,sb,play_button,ship,
            aliens,bullets):
    """响应按键和鼠标事件"""
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()
        elif event.type == pygame.KEYDOWN:
            check_keydown_events(event, ai_settings, screen, ship, bullets)
        elif event.type == pygame.KEYUP:
            check_keyup_events(event, ship)
        elif event.type == pygame.MOUSEBUTTONDOWN:
            mouse_x,mouse_y = pygame.mouse.get_pos() 
            check_play_button(ai_settings,screen,stats,sb,play_button,ship,aliens,
        bullets,mouse_x,mouse_y) 
def check_play_button(ai_settings,screen,stats,sb,play_button,ship,aliens,
        bullets,mouse_x,mouse_y):
    """
    在玩家单击Play按钮时开始新游戏
    
    参数:
    stats: 游戏的统计信息，用于控制游戏是否处于活动状态
    play_button: Play按钮的属性，包括位置和尺寸
    mouse_x, mouse_y: 鼠标点击的位置坐标，用于判断是否点击在Play按钮上
    """
    """玩家单击Play按钮时开始新游戏"""
    button_clicked = play_button.rect.collidepoint(mouse_x,mouse_y) 
    if button_clicked and not stats.game_active:
        # 重置游戏设置
        ai_settings.initialize_dynamic_settings()
        # 隐藏光标
        pygame.mouse.set_visible(False)
        # 重置游戏统计信息

        stats.reset_stats() 
        stats.game_active=True
        # 重置记分牌图像
        sb.prep_score() 
        sb.prep_high_score()
        sb.prep_level()
        sb.prep_ships()
        # 清空外星人列表和子弹列表
        aliens.empty()
        bullets.empty()
        # 创建一群新的外星人，并让飞船居中
        create_fleet(ai_settings,screen,ship,aliens)
        ship.center_ship()

def update_screen(ai_settings,stats,sb, screen, ship, aliens, bullets,play_button):
    """
    更新屏幕上的图像，并切换到新屏幕。
    
    参数:
    - ai_settings: 包含游戏设置的实例
    - screen: pygame屏幕对象
    - ship: 飞船对象
    - aliens: 外星人群组
    - bullets: 子弹群组
    """
    # 使用设置的背景颜色填充屏幕
    screen.fill(ai_settings.bg_color)
    
    # 遍历所有子弹，并绘制
    for bullet in bullets.sprites():
        bullet.draw_bullet()
    
    # 绘制飞船
    ship.blitme()
    
    # 绘制外星人群组
    aliens.draw(screen)
    sb.show_score()
    # 如果游戏处于非活动状态，就绘制Play按钮
    if not stats.game_active:
        play_button.draw_button()
    
    # 让最近绘制的屏幕可见
    pygame.display.flip()
def update_bullets(ai_settings,screen,stats,sb,ship,
        aliens,bullets):
    """更新子弹的位置，并删除已消失的子弹"""    
    bullets.update()
    # 删除已消失的子弹
    for bullet in bullets.copy():
        if bullet.rect.bottom <= 0:
            bullets.remove(bullet)
    # 检查是否有子弹击中了外星人
    # 如果是这样，就删除相应的子弹和外星人
    check_bullet_alien_collisions(ai_settings,screen,stats,sb,ship,
        aliens,bullets)
def check_bullet_alien_collisions(ai_settings,screen,stats,sb,ship,
        aliens,bullets):
    """响应子弹和外星人的碰撞"""
    # 删除发生碰撞的子弹和外星人
    collisions = pygame.sprite.groupcollide(bullets,aliens,True,True)
    if collisions:
        for aliens in collisions.values():
            stats.score+= ai_settings.alien_points * len(aliens)
            sb.prep_score()
        check_high_score(stats,sb)

    if len(aliens) == 0:
        # 删除现有的子弹，加快游戏节奏，并创建一群新的外星人
        bullets.empty()
        ai_settings.increase_speed()
        # 提高等级
        stats.level+= 1 
        sb.prep_level()
        create_fleet(ai_settings,screen,ship,aliens)    
def get_number_aliens_x(ai_settings,alien_width):
    """计算每行可容纳多少个外星人"""
    available_space_x = ai_settings.screen_width - 2 * alien_width
    number_aliens_x = int(available_space_x / (2 * alien_width))
    return number_aliens_x
def create_alien(ai_settings,screen,aliens,alien_number,row_number):
    """创建一个外星人并将其放在当前行"""
    alien = Alien(ai_settings,screen)
    alien_width = alien.rect.width 
    alien.x = alien_width+2 * alien_width * alien_number
    alien.rect.x = alien.x
    alien.rect.y = alien.rect.height+2 * alien.rect.height * row_number
    aliens.add(alien)
def create_fleet(ai_settings,screen,ship,aliens):
    """创建外星人群"""
    # 创建一个外星人，并计算每行可容纳多少个外星人
    alien = Alien(ai_settings,screen)
    number_aliens_x = get_number_aliens_x(ai_settings,alien.rect.width) 
    number_rows = get_number_rows(ai_settings,ship.rect.height,
        alien.rect.height)
    # 创建外星人群

    # 创建第一行外星人
    for row_number in range(number_rows):
        for alien_number in range(number_aliens_x):
            create_alien(ai_settings,screen,aliens,alien_number,
                row_number)
def get_number_rows(ai_settings,ship_height,alien_height):
    """计算屏幕可容纳多少行外星人"""
    available_space_y = (ai_settings.screen_height - 
                            (3 * alien_height) - ship_height)
    number_rows = int(available_space_y / (2 * alien_height))
    return number_rows
def update_aliens(ai_settings,stats,sb,screen,ship,aliens,bullets):
    """更新外星人群中所有外星人的位置"""
    check_fleet_edges(ai_settings,aliens)   
    aliens.update()
        # 检测外星人和飞船之间的碰撞
    if pygame.sprite.spritecollideany(ship,aliens):
        ship_hit(ai_settings,stats,sb,screen,ship,aliens,bullets)
    # 检查是否有外星人到达屏幕底端
    check_aliens_bottom(ai_settings,stats,sb,screen,ship,aliens,bullets)
def check_fleet_edges(ai_settings,aliens):
    """有外星人到达边缘时采取相应的措施"""
    for alien in aliens.sprites():
        if alien.check_edges():
            change_fleet_direction(ai_settings,aliens)
            break
def change_fleet_direction(ai_settings,aliens):
    """将整群外星人下移，并改变它们的方向"""
    for alien in aliens.sprites():
        alien.rect.y+= ai_settings.fleet_drop_speed 
    ai_settings.fleet_direction *= -1



def ship_hit(ai_settings,stats,sb,screen,ship,aliens,bullets):
   """响应被外星人撞到的飞船"""
   if stats.ships_left > 0:
    # 将ships_left减1   
        stats.ships_left -= 1 
        # 更新记分牌       
        sb.prep_ships()
        # 清空外星人列表和弹列表
        aliens.empty() 
        bullets.empty()
        # 创建一群新的外星人，并将飞船放到屏幕底端中央
        create_fleet(ai_settings,screen,ship,aliens) 
        ship.center_ship()
        # 暂停
        sleep(0.5) 
   else:
       stats.game_active = False
       pygame.mouse.set_visible(True)

   

def check_aliens_bottom(ai_settings,stats,sb,screen,ship,aliens,bullets):
    """检查是否有外星人到达了屏幕底端"""
    screen_rect = screen.get_rect()
    for alien in aliens.sprites():
        if alien.rect.bottom >= screen_rect.bottom:
            # 像飞船被撞到一样进行处理
            ship_hit(ai_settings,stats,sb,screen,ship,aliens,bullets)
            break
def check_high_score(stats,sb):
    """检查是否诞生了新的最高得分"""
    if stats.score >stats.high_score:
        stats.high_score = stats.score
        sb.prep_high_score()